This Application claims priority of the People's Republic of China Patent Application No. 201310657434.4, filed on Dec. 9, 2013, the entirety of which is incorporated by reference herein.
Field of the Invention
The disclosure relates to touch device technology, and in particular, to touch-sensor structures and methods of forming the same.
Description of the Related Art
Recently, touch panel techniques have been developed to be a main input method and have been popularly applied in various electronic products, such as mobile phones, personal digital assistants (PDA), and handheld personal computers. Touch sensors of a touch panel are usually formed from a first indium tin oxide (ITO) layer and a second ITO layer. The first. ITO layer forms a plurality of sensing-electrode patterns connecting with each other and arranged to form a plurality of columns, and a plurality of sensing-electrode patterns separated from each other and arranged to form a plurality of rows. The second ITO layer forms jumpers for electrically connecting the sensing-electrode patterns separated from each other and arranged in the rows.
The jumpers from the second ITO layer are usually formed by an etching process. However, if the first and second ITO layers are formed from the same material, an etching solution for etching the second ITO layer will also damage the first ITO layer. Thus, the first ITO layer is made of a crystalline indium tin oxide and the second ITO layer is made of a non-crystalline indium tin oxide. Next, an etching solution, which can only etch the non-crystalline indium tin oxide and cannot etch the crystalline indium tin oxide, is used to etch the non-crystalline indium tin oxide of the second ITO layer to avoid damaging the first ITO layer.